Recursion Base Condition Mistake
In recursion, sometimes we want the base condition to be something like this:
def recursion(first: Optional[Node], second: Optional[Node]):
if not first and not second: return True
if not first or not second: return False
Just make sure when you do this, always do the and condition first before the or.
Because if first = None and second = None, not first or not second is also True